Beverage Container With Integral Flow Control Member Having Vent And Outlet Pinhole Membranes And Safety Button

ABSTRACT

A non-spill beverage container includes a cap having a tube-like spout and a baffle mounted inside the spout, and a flow control member having a spout (first) membrane supported over the spout opening. A vent (second) membrane that is disposed adjacent to the spout and is supported over a vent opening defined in the cap. The spout and vent membranes are punctured to form multiple, substantially round pinholes that remain closed to prevent fluid flow under normal atmospheric conditions, and open to facilitate fluid flow under an applied pressure differential (e.g., when sucked on by a child). The baffle limits the differential pressure applied to the spout membrane when the container is not in use. The flow control member can only be removed from the cap by removing the cap from the container body and pressing a flexible safety button from an inside surface of the cap.

RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Patent application for “NON-SPILL CONTAINER WITH FLOW CONTROL STRUCTURE INCLUDING BAFFLE AND ELASTIC MEMBRANE HAVING NORMALLY-CLOSED PINHOLES”, U.S. application Ser. No. 11/131,721, filed May 17, 2005.

FIELD OF THE INVENTION

The present invention relates to fluid flow control devices for beverage containers, and more specifically it relates to elastic flow control members for, e.g., child sippy cups, and adult “travel” mugs and sports bottles.

RELATED ART

Sippy cups, travel mugs and sports bottles represent three types of beverage containers that utilize flow control devices to control the ingestion of beverage in response to an applied sucking force. Sippy cups are a type of spill-resistant container typically made for children that include a cup body and a screw-on or snap-on lid having a drinking spout molded thereon. An inexpensive flow control element, such as a soft rubber or silicone outlet valve, is often provided on the sippy cup lid to control the flow of liquid through the drinking spout and to prevent leakage when the sippy cup is tipped over when not in use. Adult non-spill “travel” mugs are usually fabricated from a thermally insulating material, and have a narrow spout that restricts flow of a hot beverage (e.g., coffee). A valve similar to that used on child sippy cups is sometimes incorporated into such travel mugs to prevent spills. Sports bottles are often similar to sippy cups and travel mugs in that they include container body and cap having a spout with a pull-open valve or other flow control member.

“No drip” sippy cup flow control valves typically include a sheet of the elastomeric material located between the inner cup chamber and the open end of the drinking spout that defines one or more slits formed in an X or Y pattern. As a child tilts the container and sucks liquid through the drinking spout, the slits yield and the flaps thereof bend outward, thereby permitting the passage of liquid to the child. When the child stops sucking, the resilience of the causes the slits to close once more so that were the cup to be tipped over or to fall on the floor, liquid cannot pass out of the container through the drinking spout.

One problem associated with conventional non-spill cups is that the elastomeric material used to form the slit-type “no drip” flow control valves can fatigue in the region of the slits and/or become obstructed over time, and the resulting loss of resilience can cause leakage when the slit flaps fail to fully close after use. This failure of the slit flaps to close can be caused by any of several mechanisms, or a combination thereof. First, repeated shearing forces exerted at the end of each slit due to repeated use can cause tearing of the elastomeric material in this region, thereby reducing the resilient forces needed to close the slit flaps after use. Second, thermal cycling or mechanical cleaning (brushing) of the elastomeric material due, for example, to repeated washing, can cause the elastomeric material to become less elastic (i.e., more brittle), which can also reduce the resilience of the slit flaps. Third, solid deposits left by liquids passing through the slits can accumulate over time to impede the slit flaps from closing fully.

A second problem associated with conventional non-spill cups is that the “no drip” flow control valves are typically located inside the short, straw-like drinking spout such that a small, open upper section of the spout is located above the valve. During each sip, liquid is drawn through the valve (which is pulled open by the applied suction), and the passes through the open upper section of the drinking spout into the drinker's mouth. Because the valve closes at the end of each sip (i.e., when the applied suction is terminated), a small amount of liquid is typically “trapped” (retained) in the upper section (i.e., between the now-closed valve and the open end of the drinking spout). Because the upper end of the drinking spout is open to the air, this small amount of liquid can drip or be shaken from the end of the drinking spout and create, for example spots on a light colored carpet.

Another problem associated with conventional beverage containers is that vents are required to allow air into the cup as liquid is drawn out to prevent a vacuum condition inside the beverage chamber. Conventional non-spill cups typically utilize elastomeric vent devices having slits that function in a manner similar to the conventional flow control valve used in the drinking spouts, and thus are subject to clogging and tearing problems similar to those described above with respect to the drinking spout valve.

An additional problem associated with child sippy cups is a safety requirement that no small part of the sippy cup can be easily removed and ingested by a child, and thus pose a potential choke-type hazard. To meet this safety requirement, flow control members are typically secured to the sippy cup cap in a way that requires removal of the cap from the container body in order to separate the flow control member from the cap.

What is needed is a flow control member for beverage containers (such as child sippy cups and adult travel mugs and sports bottles) that exhibits superior non-spill, no-drip characteristics. What is also needed is a flow control member that automatically adjusts its fluid flow rate to the applied suction, and avoids the clogging and tearing problems associated with conventional slit-type elastic flow control structures. What is also needed is a vent assembly that reliably regulates air pressure inside a beverage container without leakage. What is also needed is a flow control member that is securely attached to the sippy cup such that the flow control member cannot be easily removed by a child.

SUMMARY

The present invention is directed to a flexible flow control member for a beverage container (e.g., a child sippy cup, an adult travel mug, or a sports bottle) that addresses the various problems associated with conventional structures by providing at least one of a spout assembly that utilizes a baffle and membrane mechanism to eliminate leakage, an air vent mechanism utilizing a vent membrane including normally-closed pinholes, and a safety button mechanism for securely attaching the flow control member to the beverage container cap. In a disclosed embodiment, the beverage container includes a container body defining a beverage storage chamber and an upper opening, a cap mounted on the container body such that an upper wall of the cap covers the upper opening of the container body, and a flexible flow control element mounted on the cap in a manner that provides at least one of the outlet membrane disposed over a spout opening formed in the cap, the vent membrane disposed over a vent opening formed in the cap, and a safety button that is securely connected to a socket formed in the cap. Although the invention is described herein using a specific embodiment that incorporates all three of these novel features in an integrally molded flow control member, these novel features may be utilized independently.

In accordance with a first aspect of the present invention, the spout assembly includes a spout structure that utilizes a baffle disposed in a tube-like spout wall to minimize liquid pressure on an outlet membrane mounted over an end of the spout wall. The tube-like spout wall defines a flow channel extending from the upper wall of the cap to a spout opening, and the baffle, which is integrally formed on an inside surface of the spout wall. The baffle includes a wall that is substantially perpendicular to the flow channel, and defines a relatively small opening (in comparison to a width of the flow channel) between a beverage storage chamber and the outlet membrane. The baffle functions to limit fluid pressure in the region between the baffle and the outlet membrane (i.e., in the presence of a higher fluid pressure downstream of the baffle), thereby reducing fluid pressure on the outlet membrane, and thus reducing the chance of leakage through the outlet membrane. In one embodiment, the upper portion of the spout wall is flexible to facilitate flow through the outlet membrane.

In one embodiment, the outlet membrane is formed from a suitable elastomeric material (e.g., soft rubber, thermoplastic elastomer, or silicone) that is punctured to form multiple, substantially round pinholes that remain closed to prevent fluid flow through the membrane and flow channel under normal atmospheric conditions (i.e., while the membrane remains non-deformed), thereby providing a desired “no drip” characteristic. Conversely, when subjected to such an applied pressure differential (e.g., when sucked on by a child), the membrane stretches (deforms), thereby causing some or all of the pinholes to open and to facilitate fluid flow rate through the membrane, which is substantially unimpeded by the baffle under these conditions. Because the amount that the pinholes open, and the associated fluid flow through the pinholes, is related to the applied pressure differential, the present invention provides a flow control structure that automatically adjusts its fluid flow rate to the applied suction. In addition, because the pinholes are substantially round, the pinholes resist the clogging and tearing problems associated with slit-type flow control structures.

In an alternative embodiment, the beverage container utilizes the spout structure described above (i.e., including the baffle), but the outlet membrane includes a conventional (e.g., slit-like) opening. This alternative embodiment would reduce dripping through the slit-like opening due to the pressure reducing function of the baffle, but would be subject to the problems described above.

According to another aspect of the invention, the beverage container includes a vent mechanism including a vent opening that is defined, for example, in the upper wall of the cap adjacent to the spout assembly, and a vent (second) membrane that is disposed over the vent opening. Similar to the outlet membrane mounted over the spout, the vent membrane includes normally-closed pinholes that open in response to an applied pressure differential (i.e., a vacuum condition inside the cup caused by liquid being drawn through the spout), thereby allowing air to pass through the vent membrane and vent opening into the cup. The vent membrane closes when a user finishes drinking and the pinholes close, so beverage that may be located between the vent opening and the vent membrane is prevented from passing through the vent membrane, thus avoiding the dripping problem associated with conventional non-spill beverage containers. To facilitate deformation of the vent membrane (e.g., toward the cap to facilitate the venting process), the vent membrane is spaced from (e.g., supported over) the upper wall of the cap such that an air gap is present between the vent opening and the vent membrane. In one embodiment, the vent opening is disposed in a bowl-shaped depression that is integrally molded with the upper wall of the cap, and disposed below a round vent membrane, thus providing a bowl-shaped clearance for deformation of the round vent membrane to facilitate air flow into the container.

According to another embodiment of the present invention, the flow control member includes a spout portion including a relatively thick tube-like elastomeric wall that is mounted on the rigid spout wall and supports the outlet membrane over the spout opening, and a base portion that is disposed in a recess formed on the upper wall of the cap, and a safety button that extends from the base portion and is secured to the cap. The flow control member is thus secured to the cap at one end by the spout portion, which is securely mounted on the spout structure of the cap, and at its opposite end by the safety button, which extends from a lower side of the base portion and is press-fit into a socket (opening) formed in the cap. The recess formed in the cap receives the outer edge of the base portion such that an upper surface of the base portion is flush with an upper surface of the cap, thereby preventing a child from lifting the peripheral edge of the base portion and possibly removing the flow control member. In addition, the safety button is secured to the socket such that the safety button can only be easily disconnected from the cap by pushing the safety button through the socket from the underside surface of the cap, thereby meeting the safety requirement requiring that the cap be removed from the container body before the flow control member can be removed from the cap.

The present invention will be more fully understood in view of the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective side view showing a flow control structure according to a generalized embodiment of the present invention;

FIGS. 2(A) and 2(B) are top and cross-sectional side views, respectively, showing the flow control structure of FIG. 1;

FIGS. 3(A) and 3(B) are simplified diagrams illustrating tensile forces generated in flat and curved membranes;

FIGS. 4(A) and 4(B) are simplified enlarged cross-sectional views showing a pinhole formed in the flow control element of FIG. 1 in additional detail;

FIGS. 5(A) and 5(B) are cross-sectional side views showing the flow control structure of FIG. 1 during operation as a liquid flow control structure;

FIGS. 6(A) and 6(B) are cross-sectional side views showing the flow control structure of FIG. 1 during operation as an air vent flow control structure;

FIG. 7 is a perspective side view showing a non-spill beverage container including a flow control structure according to an exemplary embodiment of the present invention;

FIG. 8 is a perspective bottom-side view showing a flow control element of the beverage container of FIG. 7;

FIG. 9 is a perspective top-side view showing a cap of the beverage container of FIG. 7;

FIG. 10 a cross-sectional side view showing the beverage container of FIG. 7 in additional detail;

FIG. 11 is a cross-sectional side view showing the beverage container of FIG. 11 during use; and

FIG. 12 is a cross-sectional side view showing a spout structure according to an alternative embodiment of the present invention.

DETAILED DESCRIPTION

The present invention relates to an improved flow control member for a beverage container. The following description is presented to enable one of ordinary skill in the art to make and use the invention as provided in the context of a particular application and its requirements. As used herein, directional terms such as “upper”, “upwards”, “lower”, “downward”, “front”, “rear”, are intended to provide relative positions for purposes of description, and are not intended to designate an absolute frame of reference. In addition, the phrases “integrally connected” and “integrally molded” is used herein to describe the connective relationship between two portions of a single molded or machined structure, and are distinguished from the terms “connected”, or “coupled” (without the modifier “integrally”), which indicates two separate structures that are joined by way of, for example, adhesive, fastener, clip, threaded screw or movable joint. Various modifications to the preferred embodiment will be apparent to those with skill in the art, and the general principles defined herein may be applied to other embodiments. Therefore, the present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

FIG. 1 is a perspective view showing a flow control structure 40 according to a generalized embodiment of the present invention, and FIGS. 2(A) and 2(B) show flow control structure 40 in top plan and cross-sectional side views, respectively, where FIG. 2(B) is taken along section line 2-2 of FIG. 2(A).

Flow control structure 40 includes a molded (first) member 50 including a tube-like wall 54 defining a channel 56, a membrane 55 mounted on an upper (first) end 54A of wall 54, and a baffle (or vent hole structure) 65 mounted inside channel 56 between upper end 54A and a lower end 54B of wall 54. Wall 54 is a relatively rigid (i.e., compared to membrane 55) tube-like structure extending generally along a central axis X between upper end 54A and lower end 54B. As indicated in FIG. 2(A), in one embodiment wall 54 has a circular cross section having an inner diameter (width) D1. In other embodiments, wall 54 may have, for example, an oval, square or rectangular cross section.

Membrane 55 is relatively elastic (i.e., compared to wall 54) and is connected to wall 54 adjacent to (i.e., at or slightly inset from) upper end 54A such that membrane 55 is disposed across channel 56 to impede flow between channel 56 and an external region ER. In the disclosed embodiment, membrane 55 has a circular outer perimeter 57 that is secured to upper end 54A of wall 54. In one embodiment, elastic membrane 55 is formed from a suitable material (e.g., soft rubber, thermoplastic elastomer, or silicone) having a thickness T1 in the range of 0.01 to 0.1 inches (more particularly 0.01 to 0.03 inches), and wall 54 is formed from the same material and has a thickness T2 in the range of 0.05 to 0.12 inches. According to the present invention, membrane 55 defines a plurality of spaced-apart pinholes 59 formed using the procedure describe below such that when membrane 55 is subjected to normal atmospheric conditions (i.e., remains non-deformed), pinholes 59 remain closed to prevent fluid flow between channel 56 and external region ER through membrane 55. As described in additional detail below, pinholes 59 are also formed such that when membrane 55 is deformed (stretched) in response to an applied pressure differential between channel 56 and external region ER, pinholes 59 open to facilitate fluid flow through membrane 55. Accordingly, pinholes 59 facilitate adjustable fluid flow through membrane 55 that increases in direct relation to the applied pressure differential, thereby facilitating both a non-spill outlet membrane and a leak-proof vent membrane.

As indicated in FIG. 2(B), according to an embodiment of the present invention, membrane 55 is substantially flat (planar) in its relaxed (i.e., non-deformed or unstretched) state, and lies in a plane X-Y that is perpendicular to central axis X of channel 56. Two advantages are provided by making membrane 55 in this manner. A first advantage, which is illustrated by the simplified diagrams shown in FIGS. 3(A) and 3(B), is that a flat membrane is easier to stretch under an applied pressure than a curved membrane. In particular, as depicted in FIG. 3(A), a pressure P_(z) applied perpendicular to substantially flat membrane 55 causes membrane 55 to stretch (e.g., bow downward, as indicated by the dashed membrane 55′). Note that because membrane 55 is substantially flat, virtually all of the resultant tensile force T generated in membrane 55 is directed in the X-Y plane (indicated by component T_(x-y)), thereby generating little or no component T_(z) in the Z-axis direction until the membrane is at least partially stretched. Because the tension component T_(z) remains relatively small, planar membrane 55 is stretched (and the pinholes opened) in response to a relatively small applied pressure P_(z), thereby facilitating fluid flow through membrane 55 in response to a relatively small pressure differential. In contrast, as indicated in FIG. 3(B), a pre-curved membrane 310 generates a significantly larger tensile force component T_(z), thereby requiring a substantially larger pressure P_(z) to produce even a minimal stretching of membrane 310 from its resting position (e.g., as indicated by deformed membrane 310′, shown in FIG. 3(B)). A second advantage to provided by making membrane 55 substantially flat is that, as described below, formation of the pinholes is greatly simplified and facilitated.

Although the preferred embodiment includes a substantially flat (planar) membrane, a curved membrane may also be used, although such membrane would necessarily be relatively thin (i.e., relative to a flat membrane formed from the same material) in order to facilitate a similar amount of deformation in response to an applied pressure. A problem posed by using a relatively thin membrane is the increased chance of rupture and/or tearing of the membrane material, which may result in the unintended ingestion of membrane material.

Referring to FIG. 2(A), according to an aspect of the present invention, membrane 55 defines a plurality of spaced-apart pinholes 59 that are arranged in a two-dimensional pattern. The term “spaced-apart” is used to indicate that the pinholes are separated by regions of non-perforated membrane material (i.e., there are no holes, cracks, slits, or other significant structural weaknesses in the membrane material in the regions separating adjacent pinholes). The spacing between pinholes 59 is selected based on the membrane material such that tearing of the membrane material between adjacent pinholes is avoided under normal operating conditions (i.e., the pinholes are spaced as far apart as is practical). Note that arranging pinholes 59 in a two-dimensional pattern provides the advantage of balancing the distribution of forces across membrane 55, thereby reducing the chance of tearing of the membrane material.

According to an aspect of the present invention, wall 54 and baffle 65 have a greater rigidity than the membrane 55 such that, when an applied pressure differential is generated between channel 56 and external region ER, membrane 55 undergoes a greater amount of deformation than wall 54 and baffle 65. In one embodiment, membrane 55 and wall 54 are integrally connected to form an single-piece member 50, which is molded from a suitable material (i.e., both wall 54 and elastic membrane 55 are molded in the same molding structure using a single molding material, e.g., silicone, a thermoplastic elastomer, or soft rubber), and the increased rigidity is provided by forming wall 54 to include a thickness T1 that is greater than the thickness T2 of membrane 55. In an alternative embodiment, wall 54 may be formed at least partially from a relatively rigid material (e.g., a hard plastic), and membrane 55 may be separately formed from a relatively elastic material and then secured to wall 54.

Referring again to FIGS. 1 and 2(A), membrane 55 is depicted as being secured around its peripheral edge 57 to upper end 54A of wall 54. Alternatively, membrane 55 may be recessed into flow channel 56 to avoid damage caused, for example, by gumming or chewing on the end of flow control structure 40, provided membrane 55 is positioned between baffle 65 and external region ER (i.e., a small space is provided between baffle 65 and membrane 55 for reasons set forth below). However, significantly recessing membrane 55 creates an open upper region between the end of flow channel 56 (i.e., upper end 54A of tube-like wall 54) that may undesirably create a reservoir for small amounts of liquid that can drip after each sip when membrane 55 is utilized as an outlet valve, as described above with respect to conventional non-spill beverage containers.

In accordance with another aspect of the present invention, several pinholes 59 are formed in membrane 55 to facilitate liquid flow from channel 56 to external region ER in response to an applied pressure differential (e.g., an applied suction). As indicated in FIG. 4(A), each pinhole 59 is formed by piercing membrane 55 with a pin 410, or other sharp pointed object, such that the pinhole is closed by the surrounding elastomeric material when pin 400 is subsequently removed. In a preferred embodiment, membrane 55 is stretched in a radial direction by a force F that is sufficient to increase the diameter of membrane 55 in the range of 1 to 10 percent during the formation of pinholes 59. When the stretching force F is subsequently removed (i.e., membrane 55 returns to an unstretched state), pinholes 59 are collapsed by the surrounding membrane material to provide a reliable seal. In accordance with another aspect, each pin 410 is formed with a continuously curved (e.g., circular) cross section such that each pinhole 59 is substantially circular (i.e., does not have a slit or fold that would be formed by a cutting element having an edge). In one embodiment, pin 410 has a diameter in the range of 0.020 and 0.065 inches. Note that a pin having a diameter DIA of approximately 0.063 inches was used in a punch (8 mm depth on press) to produce successful pinholes in a membrane having a thickness of approximately 0.02 inches. The number of pinholes 59 and membrane thickness T3 determine the amount of liquid flow through membrane 55 during use for a given pressure differential, as discussed below. During operation, as described in additional detail below, membrane 55 is positioned between a liquid beverage (not shown) and an external region. While atmospheric equilibrium is maintained (i.e., the pressure on both sides of membrane 55 is essentially equal), membrane 55 remains in the unstretched state illustrated in FIG. 4(A), wherein pinholes 157 remain closed to prevent leakage. During subsequent use (e.g., when a child sucks on wall 54 like a straw), a pressure differential is generated in which a relatively high pressure on the liquid side of membrane 55 becomes greater than the relatively low pressure on the suction side, thereby causing membrane 55 to stretch outward, as indicated in FIG. 4(B). The stretching of membrane 55 causes pinholes 59 to open, thereby allowing the liquid beverage to pass therethrough. Subsequently, when the pressure differential is relieved (i.e., the child stops sucking), membrane 55 then returns to its unstretched state, and pinholes 59 return to the closed state shown in FIG. 4(A). Conversely, when membrane 55 is utilized to function as a pressure balancing vent, the ambient pressure outside the beverage container becomes greater than the pressure inside the container as liquid is drawn out (i.e., through a spout), thereby causing membrane 55 to stretch inward (i.e., toward the baffle). The stretching of membrane 55 causes pinholes 59 to open, thereby allowing air to enter the beverage container through the baffle opening, thus relieving the pressure differential. Subsequently, when the child stops sucking, membrane 55 then returns to its unstretched state, and pinholes 59 return to the closed state shown in FIG. 4(A). Note that because pinholes 59 do not include slits that can become weakened and/or trap deposits that can prevent slit flap closure, the flow control structure of the present invention facilitates leak-free operation that is substantially more reliable than that of conventional, slit-based flow control members.

Baffle 65 is an annular structure located inside channel 56 and spaced from membrane 55 such that an upper (first) flow channel region 56A is defined between baffle 65 and membrane 55, and a lower (second) flow channel region 56B is located on a side of baffle 65 that is opposite to membrane 55 (e.g., between baffle 65 and a beverage reservoir). Flow channel regions 56A and 56B communicate through opening 67, which has a relatively small diameter D2 (FIG. 2(A)). In one embodiment, baffle 65 is a substantially disk-shaped structure that is parallel to membrane 55 (when in its substantially planar, unstretched state), and opening 67 is aligned with the central axis X defined by wall 54. In alternative embodiments baffle 65 is either integrally connected to wall 54 and membrane 55 (i.e., formed as part of first member 50, as depicted in FIG. 2(B)), or fabricated separately from a second material (e.g., a rigid plastic), and inserted flow channel 56, such as described below with reference to the disclosed specific embodiment.

FIGS. 5(A) and 5(B) are cross-sectional side views showing a simplified beverage container 500A including flow control structure 40 during operation in accordance with a first aspect of the present invention in which flow control structure 40 is utilized to control the flow of a liquid beverage (BVG). Beverage container 500A includes a container body 510A having an outer wall 511 defining a beverage storage chamber 517 containing liquid beverage BVG, and an opening 519. Flow control structure 40 is mounted over open end 519 such that flow channel section 56B communicates directly with chamber 517 via open end 519, and baffle 65 is positioned between chamber 517 and flow channel section 56A. FIG. 5(A) shows beverage container 500B in an inverted position prior to use (i.e., such that atmospheric pressure is applied to the outside surface of membrane 55, and beverage BVG is prevented from leaking out of container 500B solely by flow control structure 40), and FIG. 5(B) shows beverage container 500B while a suction is applied to flow control structure 40 by an external body 530 (e.g., a child's mouth). In one embodiment, as indicated in FIG. 5(B), wall 54 and baffle 65 respectively have a greater rigidity than membrane 55 such that, when the applied pressure differential is generated between fluid flow channel 56 and external region ER (e.g., inside external body 530), membrane 55 undergoes a greater deformation than wall 54 and baffle 65 in order to, for example, prevent collapse of flow control structure 40 during use.

According to another aspect of the present invention, baffle 65 and membrane 55 combine to further enhance the no-drip/non-spill characteristic of flow control structure 40. First, the inventor discovered that providing baffle 65 in flow channel 56 limits the static pressure transmitted to membrane 55 while container 500B is held in the inverted position indicated in FIG. 5(A). More specifically, the inventor discovered that placing baffle 65 into flow channel 56 allowed the inventor to increase the flow rate characteristics of membrane 55 (e.g., reduce the thickness of membrane 55 and/or increase the size of pinholes 59), making membrane 55 more suitable for high volume flow, without increasing the tendency for membrane 55 to leak in the inverted position. The inventor currently believes that this beneficial characteristic may be produced, at least in part, by a combination of baffle 65 acting to limit the static pressure transferred to flow channel region 56A from chamber 517, and by surface tension of beverage BVG in and around opening 67. A second benefit of baffle 65 is that it impedes relatively high pressure spikes in flow channel region 56A that are generated, for example, when beverage container 500B is shaken up and down or dropped while in the inverted position shown in FIG. 5(A). The inventors discovered that, when combined with a membrane that exhibits leakage in response to such pressure spikes in the absence of baffle 65, the presence of baffle 65 significantly reduced and/or eliminated leakage through membrane 55, even when an associated beverage container is shaken vigorously. As a third benefit, referring to FIG. 5(B), when subsequently subjected to suction by external body 530, the relatively high static pressure differential creates liquid flow through membrane 55 that appears to be minimally impeded by baffle 65. Accordingly, the inventor found that by combining the increased flow rate characteristics of membrane 55 with baffle 65, flow control structure 40 provides superior non-spill, no-drip characteristics, compared to conventional non-spill designs. Further, membrane 55 operates as described above to automatically adjust the fluid flow rate through flow control structure 40 to the applied suction, and to avoid the clogging and tearing problems associated with conventional slit-type elastic flow control structures.

FIGS. 6(A) and 6(B) are cross-sectional side views showing a simplified beverage container 500B during operation in accordance with a second aspect of the present invention in which flow control structure 40 is utilized as a vent mechanism to regulate air pressure inside beverage container 500B. Beverage container 500B includes a container body 510B having an outer wall 511 defining a beverage storage chamber 517 containing a liquid beverage BVG, an opening 519, and a spout 520 having a flow channel 525. Flow control structure 40 is mounted over opening 519 such that baffle 65 is positioned between chamber 517 and membrane 55. FIG. 6(A) shows beverage container 500B in an equilibrium state prior to use (i.e., such that atmospheric pressure is equal to the air pressure in region 66B above chamber 517), and FIG. 6(B) shows beverage container 500B while a suction is applied to spout 520 by an external body (not shown). As indicated in FIG. 6(B), as beverage BVG is drawn out of chamber 517 through flow channel 525 (indicated by dark-line arrow), the resulting drop in air pressure in region 66B causes an applied pressure differential that draws (vent) membrane 55 toward baffle 65, thus opening pinholes 59 in the manner described above and allowing air from external region ER to enter chamber 517 by way of opening 67 (as indicated by dashed-line arrow). Once the air pressure in region 66B equalizes with external region ER, membrane 55 returns to the unstretched state depicted in FIG. 6(A), and pinholes 59 close to form an airtight, watertight seal between chamber 517 and external region ER. In this embodiment, baffle 65 serves as a vent opening to resist the flow of liquid into region 66A between baffle 65 and membrane 55, and as such opening 67 may be relatively smaller than the embodiment depicted in FIGS. 5(A) and 5(B) (i.e., because opening 67 is used to transmit air, not liquid).

The present invention will now be described with reference to a specific embodiment.

FIG. 7 is perspective top-side view showing a non-spill beverage container 600 that utilizes a flow control member 640 that is formed in accordance with a specific embodiment of the present invention. Container 600 generally includes a hollow cup-shaped container body 610, a cap 620 mounted on body 610, and flow control member 640, which is mounted on cap 620.

In accordance with an aspect of the present embodiment, flow control structure 640 is an integral (molded) flexible structure including a spout portion 650 having a tube-like outer spout section 654 and an outlet membrane 655 formed at an upper end thereof, a substantially flat base portion 660 having a vent membrane 665 formed thereon, and an engagement portion 670 disposed at an end of base portion 660 that is opposite to spout portion 650. Outlet membrane 655 and vent membrane 665 are constructed in the manner described above with reference to FIGS. 1-4 (i.e., outlet membrane 655 includes multiple normally-closed pinholes 659, and vent membrane 665 includes multiple normally-closed pinholes 669), where outlet membrane 655 functions to control liquid flow in the manner described above with reference to FIGS. 5(A) and 5(B), and vent membrane functions to allow air into container 600 in the manner described above with reference to FIGS. 6(A) and 6(B).

FIG. 8 is a perspective bottom-side view showing flow control member 640 in additional detail. Flow control member 640 is integrally molded or otherwise formed from a relatively flexible elastomeric material (e.g., soft rubber, thermoplastic elastomer, or silicone) using both known techniques and those described above with reference to fabrication of the pinhole membranes. Base portion 660 of flow control member 640 is a generally flat, oblong structure having a front end 660F and a rear end 660R. Spout portion 650 extends from upper surface 662 of base section 660 adjacent to front end 660F, and defines a central passage 656 that extends between membrane 655 and a lower surface 663 of base section 660. A relatively thick front flange 664 surround the lower opening of central passage 656. Also disposed on a lower surface 663 are an annular rib 667 that surrounds vent membrane 665, and a safety button 675 that is located adjacent to rear end 660R (i.e., such that vent membrane 665 is located between spout portion 650 and safety button 675). Safety button 675 includes a relatively narrow base section 676 extending from lower surface 663, a relatively wide end section 677, and defines a hollow central region 679 that facilitates insertion into a corresponding socket hole formed in cap 620 as described below.

FIG. 9 is a top-side perspective view showing cap 620 in additional detail. Cap 620 generally includes a substantially cylindrical (vertical) base portion 621, and a substantially flat or slightly domed (horizontal) upper wall 625 having an upper surface 622 that is supported on an upper edge of base portion 621. A spout structure 630 including a rigid tube-like spout wall 634 extends upward from upper wall 625, and includes therein a baffle 635 that defines a relatively small opening 637. Disposed adjacent to spout structure 630 is a bowl-shaped depression 628 that defines a vent opening 627. A socket opening 629 is defined through upper wall 625 and disposed such that depression 628 is positioned between socket opening 629 and spout structure 650. Cap 620 includes an oblong recess 680 that surrounds spout structure 630, depression 628 and socket opening 629, and has a peripheral edge 681 that is shaped to receive base portion 660 of flow control element 640 (FIG. 8). Recess 680 includes a relatively deep section 684 located at a front end 680F for receiving flange 664 (FIG. 8), and an annular groove 687 surrounding depression 628 for receiving annular rib 667 (FIG. 8). The engagement of annular rib 667 in annular groove 687 facilitates both positioning and support of vent membrane 665 over bowl-shaped depression 628.

FIG. 10 is a simplified cross-sectional side view showing beverage container 600 with flow control membrane 640 mounted on cap 620, and cap 620 mounted on container body 610.

As shown in FIG. 10, container body 610 includes a roughly cylindrical sidewall 611 having a threaded upper edge 613 defining an upper opening 612, and a bottom wall 615 located at a lower edge of sidewall 611. Base portion 621 of cup 620 has threaded inside surface that mates with threaded upper edge 613 to connect cap 620 to body 610. Sidewall 611 and bottom wall 615 of container body 610 combine with upper wall 625 of cap 620 to define an outer wall of container 600 surrounding a beverage storage chamber 617 in which a beverage is received during use. Tube-like spout wall 634 of spout structure 630 has a lower end 634B that is integrally molded to upper wall 625 and an upper (free) end that defines an upper opening 638, and defines a flow channel 636 that extends between beverage storage chamber 617 and upper opening 638. Baffle 635 is integrally molded to an inside surface of rigid spout 630 such that baffle 635 is positioned between a lower end 634B and an upper end 634A of spout wall 634, thereby effectively dividing flow channel 636 into a lower channel region 636B and an upper channel region 636A. In addition, baffle 635 defines relatively small opening 637 that facilitates fluid flow between lower channel region 636A and upper channel region 636B in the manner described above with reference to FIGS. 5(A) and 5(B).

According to another aspect of the present invention that is depicted in FIG. 10, flow control member 640 is mounted onto cap 620 such that spout portion 650 is securely (i.e., with a tight fit) mounted over rigid spout wall 634, and both cap 620 and flow control member 640 are fabricated such that side edges 661 of base portion 660 are tightly (i.e., without a significant gap) received inside peripheral edge 681 of recess 680 (see FIG. 7). In addition, recess 680 is formed to receive base portion 660 such that upper surface 662 is flush (e.g., coplanar) with upper surface 622 of cap 620 (which is also shown in FIG. 7). As further depicted in FIG. 10, relatively thick flange 664 is mounted inside deep recess section 684 such that front end 660F of base portion 660 is securely held onto cap 620 in a manner that prevents a small child from prying front end 660F upward from cap 620. Finally, rear end 660R of base portion 660 is securely held against upper wall 625 by safety button 675, which is inserted through socket opening 629 in the manner shown in FIG. 10 such that end portion 677 of safety button 675 is disposed on a lower surface 623 of upper wall 625. With this arrangement, flow control member 640 is secured to cap 620 in a manner that prevents a child from removing flow control member 640 while cap 620 is mounted on container body 610. That is, the only practical way to remove flow control member 640 from cap 620 (e.g., for cleaning purposes) is to remove cap 620 from container body 610, and then applying a force F (indicated by dark arrow in FIG. 10) against end section 677 that is sufficient to push safety button 675 through socket opening 629, thus disengaging rear end 660R from upper wall 625. With rear end 660R thus disengaged, removal of flow control member 640 is then completed by removing front end 660F from spout structure 630 (e.g., by pulling rear end 660R upward from cap 620). Because a small child typically does not have the hand strength necessary to remove cap 620 and/or to push safety button 675, the present invention provides a substantially child-proof structure that also provides the many benefits described above.

FIG. 11 is a cross-sectional side view showing the non-spill beverage container 600 in a tipped position whereby a beverage BVG is able to flow to membrane 655 by way of lower flow channel region 636B, baffle opening 637, and upper flow channel region 636A. As described above with reference to the generalized embodiment, baffle 635 and membrane 655 combine to prevent leakage when a user is not applying suction to the end of spout 634/654. When suction is applied by a user (not shown), the applied pressure differential causes membrane 655 to bend outward to open pinholes 659 in the manner described above. As beverage BVG is drawn by the user through spout 634/654, the resulting vacuum generated in storage chamber 617 is equalized by the inward deformation of vent membrane 665, which allows air to enter way of vent hole 627.

In accordance with another benefit of the present invention because membrane 655 is located at the end of spout 634/654, when a user finishes drinking and membrane 655 closes, beverage that may be retained in upper flow channel region 656A is prevented from dripping or otherwise discharging from spout 634/654, thus avoiding the dripping problem associated with conventional non-spill beverage containers.

In addition to the general and specific embodiments disclosed herein, other features and aspects may be added to the novel flow control structures that fall within the spirit and scope of the present invention. Therefore, the invention is limited only by the following claims.

For example, one or more of the novel features described herein (e.g., the vent mechanism) may be utilized separately from the other features (e.g., in conjunction with a conventional, slit type spout structure), and the features may also be used in other types of beverage containers, such as sports bottles or other hydration systems. In such alternative embodiments, the vent opening would be formed in an outer wall of the container and the vent membrane disposed over the vent hole in a manner similar to that described in the embodiments described above.

In another alternative embodiment shown in FIG. 12, a flow control mechanism 700 for a beverage container (e.g., a cup such as that described above, a sports bottle, or a hands-free hydration pack such as those produced by Camelbak Products, LLC of Petaluma, Calif., USA) includes a spout wall 734 and a flexible spout (flow control) member 750. Spout wall 734 includes a lower spout wall section 734B and an upper spout wall section 734A defining a flow channel 736 having a lower section 736B and an upper section 736A. Lower spout wall section 734B comprises a relatively rigid (e.g., hard molded plastic). A baffle 735 is integrally molded to an upper end of lower spout wall section 734B, and includes a relatively small opening 737 that communicated between lower flow channel section 736B and upper flow channel section 736A. Upper spout wall section 734A comprises a relatively flexible (e.g., rubber) upper spout wall section 734A that has a lower end attached to lower stout wall section 734B using known overmolding techniques, and an upper end that defines an outlet opening 738. Similar to the flow control member described above, spout member 750 includes a tube-like outer spout section 754 that mounts over upper spout wall section 734A, and an outlet membrane 755 that is disposed over outlet opening 738. Membrane 755 includes normally-closed pinholes formed in the manner described above. In one embodiment, lower wall section 734B is integrally molded with the cap (not shown) in the manner described above, and tube-like outer spout section 754A extends from the base portion of a flow control member (not shown) in the manner described above. In another embodiment, spout wall 734 and spout member 750 form a drinking nozzle that, for example, is provided on a sports bottle or hydration pack. The benefit of forming upper spout wall section 734A from a relatively flexible material (i.e., in comparison to lower spout wall section 734B) is that the flexible material facilitates bending of the upper end of outer spout section 754A in an inward direction (i.e., in the direction of the arrows in FIG. 12), thereby a user to enhance fluid flow through membrane 755 by biting upper spout wall section 734A/outer spout section 754A, thereby causing membrane 755 to flex in a manner that opens the normally-closed pinholes (not shown) that are formed therein. 

1. A beverage container comprising: a container body defining a beverage storage chamber and an upper opening; a cap mounted on the container body such that an upper wall of the cap covers the upper opening, wherein the cap includes a spout structure including: a tube-like spout wall having a first end and a second end, the spout wall defining a fluid flow channel extending from the first end to the second end of the spout, the flow channel having a first width; and a baffle disposed in the flow channel such that a first flow channel region is defined between a first side of the baffle and the first end of the spout wall, and a second flow channel region is located between a second side of the baffle and the second end of the spout wall, wherein the baffle defines an opening communicating between the first and second flow channel regions, said opening having a second width that is smaller than the first width of the flow channel; and a flexible flow control member mounted on the cap and including an outlet membrane mounted over the second end of the spout wall.
 2. The beverage container of claim 1, wherein the outlet membrane comprises at least one of a slit and a plurality of normally-closed pinholes.
 3. The beverage container of claim 1, wherein the outlet membrane comprises a plurality of normally-closed pinholes formed such that, when the outlet membrane is subjected to a relatively low pressure differential and the outlet membrane remains non-deformed, the plurality of pinholes remain closed to prevent fluid flow between the fluid flow channel and the external region through the outlet membrane, and when the outlet membrane is deformed in response to an applied relatively high pressure differential, the plurality of pinholes open to facilitate fluid flow through the outlet membrane.
 4. The beverage container according to claim 3, wherein the spout wall defines a central axis, wherein the outlet membrane is substantially flat and arranged perpendicular to the central axis, and wherein the baffle is parallel to the outlet membrane, and the opening is aligned with the central axis.
 5. The beverage container according to claim 1, wherein the spout wall and the baffle respectively have a greater rigidity than the outlet membrane such that, when an applied pressure differential is generated between the fluid flow channel and the external region, the outlet membrane undergoes a greater deformation than the spout wall and the baffle.
 6. The beverage container according to claim 5, wherein the flow control member further comprises a tube-like outer spout section disposed over the spout wall, wherein the outlet membrane is integrally molded with the outer spout section, and wherein both of the outer spout section and the outlet membrane comprise at least one of silicone, a thermoplastic elastomer, and soft rubber.
 7. The beverage container according to claim 1, wherein the spout wall includes a lower spout wall section formed from a relatively rigid material, and an upper spout wall section formed from a relatively flexible material, the upper spout wall section having a lower end that is secured to lower spout wall section and an upper end that defines an outlet opening, wherein the baffle is integrally connected to the lower spout wall section, and wherein the outlet membrane is disposed over the outlet opening of the upper spout wall section.
 8. The beverage container according to claim 1, wherein the flow control member comprises a substantially flat base portion disposed on the upper wall of the cap, and a tube-like outer spout section integrally connected to the base portion and disposed over the spout wall, and wherein the outlet membrane is integrally connected to an upper end of the outer spout section.
 9. The beverage container according to claim 8, wherein the upper wall of the cap defines a vent opening, and wherein the base portion of the flow control member further comprises a vent membrane disposed over the vent opening, wherein the vent membrane defines a plurality of normally-closed pinholes.
 10. The beverage container according to claim 9, wherein the cap further comprises a bowl-shaped depression disposed on the upper wall, wherein the vent opening is defined in the bowl-shaped depression, and wherein the vent membrane is disposed over and spaced from the bowl-shaped depression.
 11. The beverage container according to claim 10, wherein the cap further comprises an annular groove surrounding the bowl-shaped depression, wherein the flow control member includes an annular rib extending from a lower surface of the base portion and surrounding the vent membrane, wherein the flow control member is mounted on the cap such that the annular rib is received in the annular groove.
 12. The beverage container according to claim 8, wherein the upper wall of the cap further defines a socket, and wherein the flow control member further comprises a safety button extending from a lower surface of the base portion and engaged in the socket such that an end section of the safety button is disposed on a lower surface of the upper wall of the cap.
 13. The beverage container according to claim 12, wherein the upper wall of the cap defines a recess surrounding the spout wall and the socket, and wherein the base portion of the flow control member is mounted in the recess such that an upper surface of the base portion is flush with an upper surface of the upper wall of the cap.
 14. A beverage container comprising: a container body defining a beverage storage chamber and an opening; a cap mounted on the container body such that an upper wall of the cap covers the opening, wherein the cap includes a spout opening and a vent opening; and a flexible flow control member mounted on the cap and including a vent membrane disposed over the vent opening, wherein the vent membrane defines a plurality of normally-closed pinholes formed such that when the vent membrane is subjected to a relatively low pressure differential and the membrane remains undeformed, the plurality of pinholes remain closed to prevent air flow through the vent membrane and the vent opening into the beverage storage chamber, and when the vent membrane is deformed in response to an applied relatively high pressure differential, the plurality of pinholes open to facilitate air flow through the vent membrane and the vent opening into the beverage storage chamber.
 15. The non-spill beverage container according to claim 14, wherein the cap further comprises a bowl-shaped depression disposed on the upper wall, wherein the vent opening is defined in the bowl-shaped depression, and wherein the vent membrane is disposed over and spaced from the bowl-shaped depression.
 16. The non-spill beverage container according to claim 14, wherein the flexible flow control member includes a base portion disposed on the upper wall of the cap, and wherein the vent membrane is disposed on the base portion.
 17. The non-spill beverage container according to claim 16, wherein the cap further comprises a tube-like spout wall disposed on the upper wall, the spout wall defining a fluid flow channel communicating between the beverage storage chamber and the spout opening, and wherein the flow control member further comprises a spout portion having a relatively thick wall section integrally connected to the base portion and mounted on the spout wall, and an outlet membrane disposed at an upper end of the wall section and positioned over the spout opening.
 18. The beverage container according to claim 17, wherein the upper wall of the cap further defines a socket, and wherein the flow control member further comprises a safety button extending from a lower surface of the base portion and engaged in the socket such that an end of the safety button is disposed on a lower surface of the upper wall of the cap.
 19. A beverage container comprising: a container body defining a beverage storage chamber and an opening; a cap mounted on the container body such that an upper wall of the cap covers the opening, wherein the cap includes a socket opening defined in the upper wall, and a spout structure including a tube-like spout wall extending from the upper wall and defining a fluid flow channel therethrough; and a flexible flow control member mounted on the cap, the flexible control member including: a substantially flat base portion disposed on the upper wall of the cap, a tube-like outer spout section integrally connected to an upper surface of the base portion and disposed over the spout wall, and a safety button extending from a lower surface of the base portion and engaged in the socket opening such that an end of the safety button is disposed on a lower surface of the upper wall of the cap.
 20. The beverage container according to claim 17, wherein the cap defines a vent opening, disposed between the spout wall and the socket opening, and wherein the flow control member comprises an outlet membrane that is integrally connected to an upper end of the outer spout section and disposed over an open end of the spout wall, and a vent membrane disposed on the base portion and located over the vent opening.
 21. A vent mechanism for a container, the container including an outer wall defining a storage chamber, the vent mechanism comprising: a vent opening defined in the outer wall of the container; and a vent membrane disposed over the vent opening, wherein the vent membrane defines a plurality of normally-closed pinholes formed such that when the vent membrane is subjected to a relatively low pressure differential and the membrane remains undeformed, the plurality of pinholes remain closed to prevent air flow through the vent membrane and the vent opening into the beverage storage chamber, and when the vent membrane is deformed in response to an applied relatively high pressure differential, the plurality of pinholes open to facilitate air flow through the vent membrane and the vent opening into the beverage storage chamber.
 22. A flow control mechanism for a beverage container, the flow control mechanism comprising: a tube-like spout wall including a lower wall section and an upper wall section that collectively define a flow passage and an outlet opening; a baffle disposed in the flow passage; and an outlet membrane disposed over the outlet opening, wherein the lower wall section comprises a relatively rigid material and the upper wall section comprises a relatively flexible material, and wherein the outlet membrane defines a plurality of normally-closed pinholes. 